Closer Look at the 19" Monitor Features. Part III. Page 9

We continue our roundups of 19-inch LCD panels . Today we are going to test 13 new models from Acer, NEC, Samsung, LG, Iiyama and Philips. Besides examining each monitor in particular, we will also compare the newly released TN+Film models against the old-timers of this market, i.e. monitors on S-IPS, MVA and PVA matrices.

The monitor’s default brightness is set to 100% and contrast to 70%. Reducing both brightness and contrast settings to 46% (when the monitor was attached via the digital input) or to 49% (analog input) I achieved a screen brightness of 100nit. The monitor controls its brightness through pulse-width modulation of the power of the backlight lamps at a frequency of about 370Hz.

Unfortunately, the quality of the image produced by the L1910P left a very negative impression. Its matrix has an awfully irregular backlighting – it’s even worse than with the above-described AL1912. Non-uniform backlighting is usually visible on a black screen with dim external lighting (this is due to non-linear sensitivity of the human eye), but here you can notice it even on a light background and under bright external light. The left part of the screen, especially its top left corner, is noticeably lighter than the right part.

The monitor can’t boast a good reproduction of colors, either. Color gradients seem to consist of stripes of 5-7 millimeters wide when displayed on this monitor. This needs some clarification. I heard the opinion that the human eye can always see such stripes on the screen of any monitor. Yes, it’s true that the human eye can discern the borderline between the neighboring color tones in a gradient of any of the basic colors (red, green, blue) with the common 8-bit color encoding (8 bits for each of the three color channels, i.e. 256 grades in total). But let’s do some calculation: the width of the screen of a 19” LCD monitor is 380 millimeters. The number of grades is 256, so the width of each grade should be a little less than 1.5 millimeters. These grades should be visible on any high-quality monitor, but only if you do look for them. Moreover, the brightness of these grades is changing monotonously. That is, if the gradient is changing from left to right and from black to red, then the brightness of each N-th grade will be smaller than that of the (N+1)-th one. But when you see stripes with a width of several millimeters and when their brightness is changing irregularly (that is, there are brighter stripes on either side of the given one), then we evidently deal with defects in the electronics or the matrix of the monitor. And that’s exactly what we have with the L1910P.

The color curves, although not as bad as with the L1910S, are still far from perfect. Besides the excessively high coefficient of gamma correction (which you can adjust in the monitor’s menu, if you wish), you can see that the blue channel doesn’t distinguish between dark tones, equaling them to pure black. I constructed the diagram above using the analog connection and the default settings, but everything was almost the same with digital input and/or different settings.

I have enhanced the response time diagram here: it now shows not only the pixel rise time (i.e. the pixel’s color switching from black to a gray), but also the fall time (from a gray to black). The full pixel response time is simply a sum of these two numbers.

Here, the pixel fall time remains more or less constant, but the pixel rise time is typical for an MVA matrix: it is catastrophically high on black-to-dark-gray transitions, which makes MVA matrices less suitable for games in the first head.

This monitor is rather average in both maximum brightness and contrast ratio. You may note only two things: the contrast ratio goes down greatly when the screen brightness is low, and the contrast ratio is better when the monitor is connected via the digital input.

Overall, I have to confess that the Flatron L1910P disappointed me much. I can’t think of an application where this monitor would do well. Its irregular backlighting and bad color rendition are no good for work, while its poor response time is going to spoil the picture in dynamic games. It is possible that we’ve got a defective sample for our tests, and other samples won’t have the problem with the backlighting, but you should be anyway careful when shopping.